Visibly marked photographic film



Julyl1,l933. R. N. mus 1,917,406

VISIBLY MARKED PHOTOGRAPHIC F I'LM Original Filed Marcli l, 1929 2 11. T135118, fltoz:

Patented July 11, 1933 um'rsn sr'rss arent amen-1 ROBERT 1ST. TIIUS, OF ROCHESTER, NEVIYORK, ASSIGNOR T0 EASTMAN KODAK COM-' .PANY, OF EOOHESTE'R,NE\V YORK, A CORPORATION OF NEV] YORK i VISIBLY MARKED PHOTOGRAPHIC FILM Original application med March 1, 1929, ska-m1 This invention relates to a photographic film and more particularly to a type of film bearing visible markings, such as edge markings for indicating footage, the makers name, and the like. H i

This application is a division of my application Serial No. 343,762, filed March 1, 1929 and which was issued June7, 1932 as Patent No. 1,861,827.

' It is an object ofmy invention to provide a film bearing edge markings or other designations which are visible both before and after development;

I am aware that photosensitive material, such as motion picturefilm band, has been marked in various manners for identification: as for instance by light printing on the film, by printing with ordinary printing ink and the like. Light printing requires great care to prevent unwanted light from fogging the film and must be developed to be visible.

Ink of the usual type requires time to dry, is liable to smear or offset and may be affected by the usual fluid film treatment, as well as quite possibly affected by the film polishing and cleaning operations when such are required.

My present invention comprises a film which is marked with a fluid which overcomes the above dilficulty in that the markings are immediately visible, permanent, are not offset, and are not affected by any standard film treatment.

I have found that a visible image of high stability may be made on film through chemical action with one of the film constituents which also leaves no material which may have deleterious results on the film. By leaving an image of silver sulfide grains in the film the desired result can be accomplished. Consecutive numbers so made are particularly useful in making sound records.

It should be understood that for best results the sulfiding material must be such that it can be readily applied to the film; that it will not spread from the place applied to the film; and that it is not readily dispersed at room temperature into the atlines and transverse lines 6, which lines of No. 343,762. Divided and this application filed January Serial No. 587,748.

mosphere so as to have'a deleterious effect on the photosensitive materlal.

The deslred result may be accomplished with an ink substitute containing a material f to cause the formation of a silver sulfide image in the film; Examples of such ink substitutes are: Example 1. to 5 g. of sodium sulfide are dissolved in 100 cc. of water. This solution produces the silver sulfide image instantaneously, and the contrast of the image can be readily controlled as it is a function of the concentration of the sodium sulfide.

EaaampZe to 20 g. of sodium sulfide dissolved in 100 cc. of water and to 10 g. of sodium alginate. This solution is of fairly high viscosity, may be readily applied by suitable means, and produces a silver sulfide image immediately.

Example 3.-- /2 to 20 g. sodium sulfide in a solution of 100 cc. of water, and to 10 g. gum tragacanth.

The ink substitutes in the above cited examples may be used in various ways to mark photographically sensitive film, and for marking with any desirable data.

As a typical example of my invention as. applied to motion picture film edge markings I have indicated in the accompanying draW- j ing diagrammatic views of a marked film and a typical applicating device.

Coming now to the drawing wherein like reference characters denote like throughout I Fig. 1 is a diagrammatic fragmentary plan view of a film marked in accordance with my invention, and

parts I Fig. 2 is a diagrammatic side elevation partly in section of a typical printing device. for transferring marking fluid to the film.

In Fig. 1, a film 1 may consist of the usual cellulosic base or support coated with a gelatino silver halide emulsion 2. There may be the usual film perforations 3.

In the drawing a standard type of 35 mm. film is illustrated as having four perforations for each picture area 4, these areas being diagrammatically illustrated by longitudinal course are not visible onundeveloped film. V

taining marking fiuid 14 which may be of the type above described containing sodium sulfide with or without a viscosity producing material.

This fluid 14 may be transferred by an absorbent wheel 15 to a rotary type carrying stamp16 which contacts with the film 1 when the film is lowered by pressure roll 17 carried by the movable bracket 18.

Bracket 18 also carries guide rolls 19, and, as the film maybe threaded between rolls 17 and 19 it may be moved to and from the printing roll with the bracket. 18.,

It is customary. to mark film with the makers name or symbol as at 25, and possible footage marks or symbols 26 may be placed every sixteen picture frames if desired. An ordinary type of numbering stamp may be used for this purpose if desired as my marking fiuid maybe of the proper viscosity to use with the commercial article.

It is also possible, when required, to furnish markingfluid of low'viscosity for use in hand marking with ordinary pen as used with ordinary ink.

But whatever the way my marking fluid is applied, it produces, by changing the film coating to silver sulfide, a permanent, visible record which will withstand the usualfilm treatments.

Having thus described my invention, what i outside of the central picture area, and visible silver sulfide markings on said edge area.

3. As an articleof manufacture, a photographic film having a central area adapted to receive a plurality of motion picture images, perforated areas adjacent both sides of the picture area, and a plurality of visible silver sulfide images in said last mentioned areas adjacent said perforations.

l. As an article of manufacture, a photographic film band having an image areaand a plurality of visible numbers composed of silver sulfide spaced at intervals along said band outside of said image area.

Signed at Rochester, New York, this 14th day of January 1932.

ROBERT N. TITUS. 

